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A Stereoselective [3+1] Ring Expansion for the Synthesis of Highly Substituted Methylene Azetidines.

ABSTRACT: The reaction of rhodium-bound carbenes with strained bicyclic methylene aziridines results in a formal [3+1] ring expansion to yield highly substituted methylene azetidines with excellent regio- and stereoselectivity. The reaction appears to proceed through an ylide-type mechanism, where the unique strain and structure of the methylene aziridine promotes a ring-opening/ring-closing cascade that efficiently transfers chirality from substrate to product. The resultant products can be elaborated into new azetidine scaffolds containing vicinal tertiary-quaternary and even quaternary-quaternary stereocenters.

SUBMITTER: Schmid SC

PROVIDER: S-EPMC5693379 | biostudies-literature | 2017 Sep

REPOSITORIES: biostudies-literature

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A Stereoselective [3+1] Ring Expansion for the Synthesis of Highly Substituted Methylene Azetidines.

Schmid Steven C SC Guzei Ilia A IA Schomaker Jennifer M JM

Angewandte Chemie (International ed. in English) 20170901 40

The reaction of rhodium-bound carbenes with strained bicyclic methylene aziridines results in a formal [3+1] ring expansion to yield highly substituted methylene azetidines with excellent regio- and stereoselectivity. The reaction appears to proceed through an ylide-type mechanism, where the unique strain and structure of the methylene aziridine promotes a ring-opening/ring-closing cascade that efficiently transfers chirality from substrate to product. The resultant products can be elaborated in ...[more]

PMID: 28834110

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